Grinding-mill.



R. M. WILLSON.

GRINDING MILL.

APPLICATION FILED mu 6. 1914.

1, 1 37,685, Y Patented Apr. 27, 1915.

54/! 1 1755.545 I flya/wzf w' 7 4% way; wizw/zw THE NORRIS PETERS c0.F'HOID-LITHQ. WASHINGTON, D, c.

ROBERT M. WILL-SON, 0F RIVERSIDE, CALIFORNIA.

GRINDING-MILL.

Specification of Letters Patent.

Patented Apr. 27, 1915.

Application filed July 6, 1914. Serial No. 849,145.

To all whom it may concern:

Be it known that 1, ROBERT MARTIN WILL- SON, a citizen of the United.States, residing at Riverside, in the county of Riverside, State ofCalifornia, have invented new and useful Improvements in Grinding-Mills,of which the following is a specification.

This invention relates toa grinding mill, and particularly pertains to amill for grinding ores of the arrastre type.

It is the object of this invention to provide a mechanically drivenarrastre in which the slimes are discharged centrally during thegrinding operation.

Another object is to provide an effective means for rotating thearrastre arms by which the drags are moved over the materials to beground.

A further object is to provide an arrastre which is simple inconstruction and which can be readily installed and worn parts easilyremoved and replaced.

A further object is to provide an efficient bearing for the arrastrearms by which slight frictional wear and ease of operation are insured.

The invention is illustrated in the accompanying drawings, in which:

Figure 1 is a perspective view of an larrastre constructed in accordancewith this invention. Fig. 2 is a longitudinal section on the line 2-2 ofFig. 1, as seen in the direction indicated by the arrows. Fig. 3 is a,detail horizontal section on the line 3-3 of Fig. 2. Fig. 1 is anenlarged detail section and elevation of the central supporting columnillustrating the construction of the central slime discharge.

More specifically, 6 indicates the floor of the arrastre which ispreferably formed of concrete and 7 designates the annular verticalwalls of the arrastre mounted on the floor 6 and extending a suitableheight thereabove. This wall 7 is preferably formed of concrete and isconstructed with an internal upwardly extending flange 8 and an externalflange 9 projecting from its upper edge; an annular channel 10 beingformed between the flanges 8 and 9, the bottom of which constitutes atrack or runway for a series of rollers 11 mounted on brackets 12carried by the arrastre arms 13. If desired, a metallic rail 14 may bemounted in the channels 10 on which the rollers 11 may travel.

The inner flange 8 projects a short dis tance above the flange 9 and itsouter wall slopes outwardly from its upper edge to its lower edge sothat oil or grease deposited thereon will readily drain to the channel10. The upper edge of the outer flange 9 is formed with an annulargroove 16, which is provided for the purpose of collecting such oil orgrease as may splash from the channel 10 to prevent its spreading on theouter face of the wall 7.

Formed centrally of the annular walls 7 is a post 17 having ahorizontally extending annular flange 18 on its upper end, and extendingupwardly from the post 17 is a rigid spindle 19 on which a hub 20 isrevolubly mounted. The hub 20 is formed with an annular bottom flange 21formed on its underside with an annular runway 22 and is supported on aseries of ball bearings 23 carried in a runway 24 on the upper end ofthe post 17. The inner ends of the arrastre arms 13 are rigidly mountedon the flange 21 and extend radially from the hub 20 as. shown inFig. 1. The outer ends of the arrastre arms 13 connect with a ring 25disposed above the outer flange 9 on the arrastre wall the ring 25 beingformed with a channel 26 on its outer periphery adapted. to receive acable 27 by which the arrastre wheel comprising the arms 13 and the ring26 is rotated around the spindle 19. The cable 27 is crossed, as shownin Fig. 1, and after passing around direction pulleys 28 and 29 ispassed around a driving sheave 30 mounted on a drive shaft 31 adapted tobe rotated from any suitable source of power through a driving pulley 32thereon.

The direction pulleys 28 and 29 are carried by rope connections 33 and34 to posts 35 and 36, which connections are adjustable to tighten orslacken the driving cable 27 as desired. Connected to the arrastre arms13 are the usual drags 37 which may be formed of any suitable weightedmaterial and are attached to the arms 13 by means of chains 38 or otherflexible connections.

Surrounding the central post 17 and spaced therefrom at its base is ametallic cylinder 39 rigidly secured to the floor 6 and terminating at asuitable point thereabove. Secured to the upper end of the cylinder 39and extending thereabove is a screen cylinder 10, the upper end of whichis attached to the flange 18; this screen cylinder forming a screeneddischarge outlet centrally of the arrastre. Formed in the floor 6between the metallic cylinder 39 and the post17 is a discharge opening41 which communicates with a conduit 42 leading to anysuitable point ofdischarge.

Formed in the wall 7' is an outlet or drain opening 43 which is normallyclosed by means of a gate 44 and is provided with'a screen 45; the gate44 being opened when it is desired to drain the space inclosed by theWall 7. T

In the operation of the invention, the materials to be ground are placedon the floor 6 within the Wall 7 in any desired manner, together withthe necessary Water, which may be fed to the arrastre in any desiredmanner. The arrastre wheel is then rotated by driving the shaft 31 fromany desired source of power; the rotation of the shaft 81 beingtransmitted to the arrastre wheel through the cable 27. On the rotationof the arrastre wheel the drags 37 will be hauled over the materials andthe floor 6 thereby subjecting them to a grinding and pulverizingaction. The centrifugal action of the drags tends to force the largerparticles of the materials outwardly toward the wall 7, While the finerparticles will be forced inwardly toward the post 17. Such materials asare held in suspension in the water and are of sufiicient. fineness willpass throughthe screen 40 and be discharged through theopening 41 andconduit 42 and thereafter subjected to any further treatment desired.

To prevent oil or grease from the bearings on the post 17 from gettinginto the arms tre, an annular groove 46 is formed on the top of the post17 around the runway 24. The arrastre floor 6, annular wall 7 and post17 are built of concrete, suitably reinforced if desired, and the innerface of the wall 7 and the surface of the floor 6 are lined with slabsof rock 47 to form a hard grinding surface.

WVhat I claim is:

1. In a grinding mill, the combination of and hub around the spindle.

a horizontally revoluble member, an annular 7 wall on which the outerportion of the revoluble member is supported, a plurality ofdragscarried by the revoluble member for grinding materials within thespace inclosed by the wall, and means through which the ground materialsmay be discharged centrally of said space.

2. An arrastre, comprising an annular wall, a post disposed centrally ofthe space inclosed by the wall, a spindle on said post, an arrastrewheel revolubleon said, spindle, and having a bearing on the annularwall, a plurality of drags carried by the arrastre wheel for grindingmaterials within the space inclosed by' the wall, and means arms, acable arranged in the groove on said ring, and means for driving saidcable to rotate the ring and arms. 7

4. Any arrastre, comprising an annular wall formed with inner and outerupwardly projecting flanges on'its upper, edge, a rail arranged betweenthe flanges, a ring disposed above the wall, a plurality of armsconnected to said ring, a hub to which the inner ends of said arms areattached, a spindle around which said hub is revoluble, rollers on saidarms adapted to travel onthe rail, and means for rotating the ring, armsIn witness that I claim the foregoing I have hereunto subscribed my namethis 5th day of June, 1914. v V I I ROBERT M. WILLSON. Witnesses: 7

MARGUERITE BATES, MARIE BATTEY.

Copies of .this patent maybe obtained for five cents each, by addressingthe Commissioner of Patents, Washington, I). 0. i

